Due to actualization of environmental problems in recent years, hybrid cars and electric cars have spread. Furthermore, as an air conditioner which is applicable to such a vehicle, there has been developed an air conditioner which includes a compressor to compress and discharge a refrigerant, a radiator (a condenser) disposed on a vehicle interior side to let the refrigerant radiate heat, a heat absorber (an evaporator) disposed on the vehicle interior side to let the refrigerant absorb heat, and an outdoor heat exchanger disposed outside the vehicle interior to let the refrigerant radiate or absorb heat, and which changes and executes respective modes such as a heating mode in which the refrigerant discharged from the compressor radiates heat in the radiator and the refrigerant by which heat has been radiated in this radiator absorbs heat in the outdoor heat exchanger, a dehumidifying mode in which the refrigerant discharged from the compressor radiates heat in the radiator and the refrigerant by which heat has been radiated in the radiator absorbs heat in the heat absorber, and a cooling mode in which the refrigerant discharged from the compressor radiates heat in the outdoor heat exchanger and absorbs heat in the heat absorber (e.g., see Patent Document 1).
Additionally, an electric car or part of hybrid cars is connected to an external power source (a charger) installed at home or in a power supply facility (a power supply point), whereby a battery can be charged (so-called plug-in). When the battery is charged by such plug-in, the present invention can contribute to fuel efficiency improvement especially in the hybrid car.